Electric switch



Oct. 16, 1951 '(3, J, MEUER 2,571,467

ELECTRIC SWITCH Filed Oct. 29, 1948 3 Sheeas-Sheet 2 MQMM SM G. J. MEUER ELECTRIC SWITCH Oct. 16, 1951 5 Sheets-Sheet 3 Filed Oct. 29, 1948 L L 6a? 66 56 56 76 56 4| 56a 2666:, 65 57 4l 64 56C ez? 6l Patented Oct. 16, 1.951

Unirse STATES PAT-ENT oFFICE George J. Mener, Milwaukee,4 assignerto Cutler-Hammer, Inc.,.M1lwaukee, Wis., a cor'- poration of Delaware Application canteras, 194s,.seria1N. 57,378

70mm. (o1. 2064153) This invention relates to improvements in electric switches and more rparticularly switches adapted to control alternating currents. A

A primary object ofthe present invention is to improve the details of construction and assem-A bly of the parts of switches of the aforementioned character. v ,5 o

Another object istoprovidean improved form of switch base which is common to all of the forms of `switches herein contemplated.

Another object is to provide a novel arrangement of switchfbase in respect ofnalording a substantially dust-tight enclosure of its interior wherein is carried the stationary contacts, spring biased contactors and actuating elements associated with the latter. y l

Another object is to provide a switch base with improved construction and arrangement of its wiring terminals, and .1.

Another object is to provide in connection, with non-latching and latching trigger type operat, ing, superstructures for electric switches, ime proved arrangement of the same and their operating connections to aord compactness of the switch assemblies so as to facilitate mounting in tool-handle housings or receptacles.

Other objects and advantages of the invention will hereinafter appear.

The switch base, which is-common to all the various forms of switches herein contemplated, in certain respects is similar to that disclosed in the Krieger Patent 2,295,688 issued September 15, 1942, and certain forms of operating superstructures herein contemplated are similar in certain respects to forms disclosed in my Patents 1,889,259 issued November 29; 1932; 1,977,078 issued October 16, 1934; and 2,089,032 issued August 3, 1937.. 1 t

The accompanying drawingsv illustrate certain embodiments of the invention which will now be described, it being understood that the embodiments illustrated are susceptible of modiiication in respect of certain structural details thereof without departing from the scope; of the appended claims.

In the drawings:

Figure l is an elevational view of a switch (twice normal scale) showing the bottom side of a molded insulating base, which is common to all of the various switches hereinl disclosed-the Contact wiring terminals and an auxiliary wiring lug being shownY in position, together with one preferred form of trigger type switch operatr-` ing mechanism which is shown in section,

. Fig. 2 is a sectional view,onthe line 2--2 of 2 Fig. 1 with the trigger mechanism being shown in elevation. Fig.3 is avsectional view, on the line 3-3 of Fig. Al showing the switch contacts and wiring terminals.

Fig. 3a is a fragmentary ViewY of the lower right hand corner portion of the bottom side 4of the switch baseshown in Fig. l but with the terminal member, wiring lug and securing rivets removed. p

Fig. 4 is a view of the upper surface of the switch base shown in Fig. 1 with the trigger lever and associated operating mechanism cut away. Fig. 5 is a sectional View, on the line 5--5 of Fig; 2. 4, Y

Fig. 6 is a fragmentary sectional view of one corner-of the switch lbase to further illustrate the wiring terminal associated with certain of the switch contacts.

Fig. 7 is a View similar to Fig. 1 showing a modified form of switch, wherein the trigger op-r erating mechanism is provided with a latch and wherein the wiring lug is omitted.

Fig. 8 is a. fragmentary view of the switch shown in Fig- ,7, viewed at lright angles thereto, and with portions of the operating mechanism and mounting means therefor being shown in section. v Fig. 9 is a view in longitudinal section of another modied form of the switch wherein a toggle lever type of operating mechanism is provided together with a three-hole type mounting bracket, and Fig. l0 is a fragmentary view partially in section to illustrate another modified form of switch wherein a toggle lever operating mechanism is provided together with a one-hole mounting bracket.n

Referring to the switch shown in Figs. 1 to 6,- generally considered it comprises a switch base in which are carried stationary and movable contacts and art operating superstructure of the trigger type The larrangement of the stationary and movable contacts in the switch base is similar to that disclosed in the aforementioned Krieger patent although differing therefrom in respect` of certain details. As will now be describedv the switch base of the instant form of switch differs from that disclosed in the Krieger patent in respect of its wiring terminals and the means utilized to enclose the upper surface of the switch base. Y

More Vparticularly considered the numeral I5 designates a preferredform of molded insulating baseaformedl of any suitable insulating material such'asf-a `melamine resin. Opening tothe upper surface Ia of base I5 are three longitudinally parallel recesses I6, Il, I8 as best shown in Fig. 4. The opposite side recesses I6 and I8 are suitably formed, as best shown in Fig. 3, to accommodate respectively pairs of stationary contact members I9, I9 and cooperating spring biased substantially U-shaped bridging contactors 20, 20 which underlie respective pairs of the contact members I9, I9. On their bottom surfaces contact members I9 are provided with contact tips I9a which are preferably formed of silver or a silver base material and which are suitably secured to members I9 as by spot welding. Movable contactors 20, 28 are provided on the upper surfaces of their outwardly extending arms with contact tips 28* which are adapted to engage with the stationary contact tips I9. Each of the movable contactors 20 has bearing against its intermediate portion one end of a coil compression spring 2I which spring bears at its opposite end against the bottom of the respective recess I6 or I8 as best shown in Fig. 3. Contact members I9 are secured within recesses I6 and I8 by rivets 22 which extend through suitable openings formed in base I5 to the bottom side of said base.

A iiat punched insulating plate 23 is accommodated edgewise and transversely of recesses I6, I1 and I8 in alined notches 24 and 25 which respectively interconnect recesses I6I1 and recesses I1-I8. Also end portions of plate 23 are accommodated within the U-shaped intermediate portions of contactors 20 to bear upon said contactors as best shown inFigs. 3 and 4.

Overlying the upper edge of plate 23 and located in base recess I1 is a cam operating memf ber 26. Cam 26 comprises a strip having a flat portion 26 which overlies the upper edge of plate 23 and which at one end is of T-shape, as best shown in Fig. 4. The T-shape end of portion 26a is located within a corresponding T-shape portion I1a of recess I'1 opening to the upper surface I5 of base I5. The bottom wall of recess Ila slopes upwardly from a shoulder of recess I1 at a slight angle toward the upper surface I5 of the base, as best shown in Fig. 2. `The cam 26 has a portion 26b which projects'upwardly from the free end of portion 26a at a right angle therefrom and which extends through a small rectangular opening formed in a. exible rubber or rubber like diaphragm 21 of sheet form that overlies the upper surface I5 of the base. Further the cam 26 has at the upper end of portion 261 and exposed above the diaphragm 21 a, portion 26 which bears substantially at a right angle to portion 26b and which is in a substantially parallel and overlying relation to the portion 26. Additionally cam 26 has a portion 26d extending from the portion 26 at an obtuse angle toward the portion 26, said portion 26l having a free end. Adjacent its free end the portion 26d is concavely curved in its longitudinal dimension.

Diaphragm 21 overlying upper surface I5'L of the base affords a substantially dust-tight enclosure for recesses I6, I1, I8 and I1*l and for the notches 24 and 25. It also affords retention of the T-shape end of cam 26 within recess I1n wherein said cam is afforded pivotal bearing support.

As will be apparent when cam 26 is pivotally moved inwardly of base I5 it causes plate 23 to move downwardly in said base against the bias of springs 2|, 2I bearing upon contactors 20, 20, thereby effecting disengagement of the contact tips 20a of the contactors from contact tips I9* of the stationary contact members I9 for circuit interruption. When the cam 26 is relieved of downward pressure the springs 2| act on the contactors to reengage them with the stationary contact members and to return said cam to its outer extreme position.

Whereas in the aforementioned Krieger patent a molded insulating cam member is utilized I ilnd that the cam 26, formed as by the stamping and punching of a strip of sheet metal, is particularly useful in conjunction with the diaphragm 21.

Base I5 on its outer face paralleling the aforedescribed recessed face is provided with a longitudinally extending, substantially rectangular central rib I5b as best shown in Figs. 1 and 2. Intersecting the rib I5b at a point midway between its opposite ends and lying on opposite sides thereof are ribs I5, |5, whose form is best shown in Figs. 1, 3 and 5. The ribs I5b and I5c separate, and act as barriers between, the four corner portions 28, 29, 30 and 3I of the surface of the base from which said ribs project.

'I'he base surface portions 28, 29, 30 and 3| are alike in form. By way of example, as best shown in Figs. 1, 3 and 6, the portion 28 has surfaces 28* and 28 lying in different parallel planes and a sloping interconnecting surface 28b which as shown does not meet the surface 28 exactly but is slightly offset therefrom, the intermediate surface being perpendicular to surface 28. As best shown in Figs. 3 and 3, surface 28b has formed therein an opening which gives access to a recess 28 in the base, said recess having parallel side walls and intermediate walls meeting to give the recess a triangular form. Also, as best shown in Figs. 3, 3* and 6, .the surface 28 has a small rectangular opening therein giving -access to a. recess 28f extending linwardly of said base for a short distance, the recess to receive with a snug ilt a. rectangular part. Each of the other recesses 29, 38 and 3I have surfaces and recesses like those aforedescribed in connection with portion 28 and in each instance such surfaces and recesses are designated by identical subscripts.

As best shown in Figs. l, 3 and 6, like terminal members 32 are mounted on portions 28, 29, 30 and 3I of the base. Each terminal member 32 is provided with la reduced rectangular end extension 32 to project into one of recesses 28f, 29', 30f, 3If, such extension being an integral part of a portion 32b carrying a binding screw 39, the shank of which extends into one of the recesses 28, 29, 38, 3I. Portions 32 of said terminal members 32 are perforated to accommodate the Shanks of the rivets 22 which in addition to their function aforedescribed afford rigid securement of members 32 to base I5 and electrical connection of each terminal member with a stationary contact member I9.

As will be noted the arrangement of terminal members 32 is substantially different from that disclosed in the aforementioned Krieger patent. The instant arrangement facilitates the making of wire circuit connections with the switch and prevents disturbing the alinement and positioning of the stationary contact members I9 within the switch base. Any strains occurring in the making of wire connections are localized to the terminal members 32. It will also be noted by those skilled in the art that the arrangement of terminal members 32 provides access for making the equivalent of bottom and/or end wiring connections therewith.

An auxiliary wiring lug 33 is secured to the base I5 centrally with respect to the four terminal members 32 as best shown in Figs. 1, 2 and 5. Lug 33, which is preferably formed by stamping and punching of a strip of "brass, is provided with a flat, elongated oval shape portion 33a which engages with the rib |5EL of base I5 between the ribs I5C, I5c thereof. Lug 33 is also provided with small rectangular extensions 33h, 33h which project at a right angle to the portion 33a on opposite edges of the latter. A circular opening is provided in the portion 33a midway between its ends to accommodate a short cylindrical boss I5f of base I5 which extends outwardly between the ribs |56, I5".

Two other circular openings of smaller diameter are formed in the portion 33a on opposite sidesA of the aforementioned 'opening- A hollow rivet 34 penetrates lug 33 through one of the last mentioned openings, said rivet ybeing contained in a recess I5g of base |5 and extending outwardly from said bas-e. Recess I5g in the instant form of switch is broached through to communicate with the recess I'I, the bottom wall of which is of slightly greater width `than that of recess |53. Rivet 34 is provided with a rectangularly shaped head snugly tting recess I'I and with a shank extending through recess I5g and lug 33 to have its end upset over the outer surface of lug 33 to thereby secure the latter to base I5. Rivet 34 is suitably threaded internally to receive a binding screw 35. The other of said openings in lug 33 -is suitably threaded to receive a binding screw 36 which extends inwardly of base I5 within a clearance recess I5h formed in the latter. A thin fiber insulating member 3T having a shape like that of the portion 33a of lug 33, but at all points extending la, substantial disw tance therebeyond, -is interposed 'between lug 33 and base I5.

As will be understood :the lug 33 and the parts associated therewith have no electrical connection with the terminal members 32 or stationary contact members I9 and is provided as an auxiliary bussing lug or wiring bracket for convenience in anchoring' wires to the switch. Lug 33 and the part-s associated therewith may be omitted if desired as shown in `connection with the modified forms of switches hereinafter lto be described.

A combined cover and frame member 38, preferably formed by punching and stamping a sheet metal plate has a portion 38a which in part overlies the surface I5EL of base I5 and portions 38h and 38 which extend beyond said base. As viewed in Fig. 5, .the portion 389- of said member is of substantially inverted channel shape in vertical cross section. As best shown in Fig. 2, the portion 38EL has a pair of openings 39 and 40 extending therethrough and formed for countersinking of the upset ends of rivets 4I which provide for securement of member 38 to base |5. Openings 39 and 40 register respectively with openings 42 and 43 extending through base I5 and being enlarged adjacent the surface of the base to provide inset annular shoulders for abutment by the heads of the rivets 4 I.

A stiff ber insulating plate 44 coextensive with the surface I5a of base l5 and diaphragm 27 and having a rectangular central opening 44a is positioned between the portion 38a of member 38 and a flexible fiber member 45, overlying diaphragm 2l. Members 44 and 45 have openings to accommodate the Shanks of rivets 4|.

Although not shown in the drawings, the member 45 in practice would commonly extend beyond the outer side walls of base I5 as viewed in Fig. 1

to be bent to form an insulating envelope around4 the bottornof base" I5 to protect against ground# ing of wires connected to the terminal members 32 and the lug 33.

As best shown in Figs. 1 and 2, the member 38 at the end of portion 38e turns inwardlyI providing a portion 38b paralleling the end of base |5 and at the end of portion 38b-turns to provide a portion 38c lying in a plane paralleling that of portion 38a. Extending from the portion 38c `is a vhalfmoon shaped lug 38d which depends at an angle to the plane of portion 38C. The portion 38 merges with a portion 38e which issli'ghtly offset therefrom and also with a portion 38f whichis offset therefrom to a greater degree. A lug 38g. sheared from the portion 38c projects 'at a, right angle thereto and provides support for a coile spring 46.

A contactor actuating member 41, preferably formed from a sheet metal plate by punching and stamping, has a portion 47a reciprocably mounted in the channel section of portion 38a as best shown in Figs. l, 2 and 5, said portion 4Ia having a slot 471 freeing it for reciprocation without interference by the penetrating connection vcomprising right hand rivet 4|. Portion IIISL has at its free end a rectangular extension 4'Ic to bear upon and to be moved along the portions 26C and 26d of cam 25, said extension being outwardly turned and projecting into a channel provided in part 38a of member 38. Portion 4'Ia of member V4I is connected with a portion 4'IlI which bears at a right angle thereto and which lies in a parallel relation with the portion 38b of member 38. Portion 47d in turn is connected with a portion 47e which bears at a right angle therefrom in a parallel relation to the portion 41e, and which along a greater portion of its length is of reduced width. Adjacent its free end the portion 47e is provided with a circular opening through which extends a reduced portion of a tubular bushing 48. Bushing 48 is rigidly secured to portion II'Ie by upset'- ting of the end of said reduced portion of said K bushing which extends beyond said portion 47e.

For actuation of member 41 there is provided a trigger type actuator 49 which is similar in form to certain vtrigger actuators disclosed in my Patents l,889,259, 1,977,078 and 2,089,032. However, as will now be described the instant trigger actuator differs in respect of certain details .of construction, its operating connections and the way in which it is mounted with respect to the switch base.

Actuator 49 generally considered is of saddleshape. More particularly it is U-shaped in transverse vertical cross section and comprises vparallel depending side portions 49a and 4Gb interconnected by a portion 49 which is concavely curved in its longitudinal dimension to afford good finger gripl Actuator 49-is mounted in a straddling relation to the portions 38C, 38d, 38e and 38f of member 33 and is afforded pivotal sup port by a pivot pin 50 whichextends through alined openings formed in the side portions 49a and 49b of said actuator and through .a hollow bushing 5| penetrating the portion 38e and being secured thereto in the manner aforeindicated for the bushing 48. Pin 50 is provided at one end with an enlarged head which bears against the outer surface of portion 49a and at its opposite endis upset over Vthe outer surface of the portion 49b thereby being secured against axia1 movement. The portion 49 is depressed at a point between the portions 49a and 4I]1a to form an abutment for spring 46. Portions 49a and 491 are provided with additional alined openings for a cylindrical pin 62 which extends'through the bushing 48 and which is secured to the actuator in the manner aforeindicated for the pin 50. The shank diameter of pin 52 is substantially less than the inner diameter of bushing 48.

As will be understood spring 46 biases actuator 48 for pivotal movement in the clockwise direction as viewed in Fig. 1, but such movement being limited by engagement of the shank of pin 52 with the marginal side of portion 38f of member 38.

As shown in Fig. 1, two circular openings 53 and 54 are provided in portion 38c of member 38 to provide for attachment of the switch assembly within a tool handle or other housing as by bolts or screws which are accommodated by said openings.

As the switch stands in Figs. l and 2, the member 41 is moved to its extreme left position due to the bias of spring 46 which acts thereon through actuator 49, pin 52 and bushing 48. As aforedescribed when member 41 is in such position, its portion 41c engages with the portion 26c of cam 26 and thereby effects disengagement of the contactors 28 from the stationary contact members I8. As will be appreciated, in its extended relation shown in Fig. 1 spring 46 must be strong enough to overpower the springs 2|, 2| in the switch base to collapse the same.

When the actuator 48 is pivotally moved against the bias of spring 46 in the counterclockwise direction as viewed in Fig. 1, the pin 52 is caused first to take up the play thereof within the bushing 48 and then to engage the opposite wall of bushing 48 and move member 41 to the right. When member 41 is moved sufficiently far to the right its portion 41c moves out of engagement with the portion 26c of cam 26 and onto the portion 26d of the latter. Then the bias of springs 2|, 2| acting through contactors 20, 20, member 23 and cam 26 cause member 41 to move to the right with more or less snap action. As a result the contactors 20, 20 engage with the stationary contact members I8 and the bushing 48 moves free of the shank of pin 52 until it again re-engages with the same on the opposite side. The subsequent re-engagement of bushing 48 with pin 52 provides an audible signal and a tactilly perceptible signal which is transmitted through pin 52 and actuator 48 to indicate that the switch has been operated to its circuit completing condition. Actuator 48 may only be moved against 4the bias of spring 46 to a limited extent and is moved to such limit when the bottom surface of its portion 49c engages with the lug 38d of member 38. Releasing the actuator 48 for movement under the bias of spring 46 effects return of the switch to its circuit interrupting condition aforedescribed.

The modified form of switch illustrated in Figs. 7 and 8 is identical in respect of the switch base I5, the contact mechanism carried within said base, the cam operating member 26, diaphragm 21, insulating plate 44, flexible insulating member 45 and the wiring terminals 32 shown and described in connection with the switch illustrated in Figs. 1 to 6, with the exception that the wiring lug 33 and its associated binding screws 35 and 36, rivet 34 and fiber insulating plate 31 are omitted from base I5 and the recess |58 is not broached through to the recess I1 in base I5 as aforedescribed. As will now be described the modified form of switch differs principally in respect of its trigger actuator which is of the latching type.

As shown in Figs. 1 and 8, the switch is provided with a combined cover and frame member 56 having a portion 56l which overlies the insulating plate 45. Portion 563L is essentially of the same channel-shape cross sectional form as the portion 38"L of member 38 aforedescribed and is provided with a pair of spaced openings 51 and 58 which register with corresponding openings formed in diaphragm 21, plate 44, member 45 and openings 42 and 43 in base I5. Somewhat elongated depressions are formed about the openings 51 and 58 in portion 56tl to accommodate the upset ends of the rivets 4| which secure member 56, plate 44, member 45 and diaphragm 21 in assembled relation to the surface I5Il of base I5.

Member 56 is provided with portions 56b and 56c which are integrally formed with the portion 56a and which extend to the left and right beyond the base I5 respectively. Portion 56 is connected with portions 56d which is offset therefrom as shown in Fig. 8. A lug 56f extends from the portion 56 at a right angle thereto to provide an abutment for spring 58. Portion 56d has fixed thereto as by riveting a perpendicularly disposed post 6I projecting in the same direction as spring abutment lug 56f.

An operating member 62 is provided with a portion 62a slidable within the channel section of portion 56a of member 56. A portion 62", similar in form to the portion 48c of member 48 aforedescribed, is integrally connected with the portion 62a and like said portion 48c is adapted to engage with the portions 26 and 28d of cam 26.

Also member 62 is provided with a portion 62c which extends from the portion 62a with offset therefrom as shown in Fig. 8; the contour of portion 62c being best shown in Fig. '1. Portions 62a and 62b have a slot 63 therein to afford it for reciprocation clearance from the parts to pass through openings 64 and 65 in member 56 as well as from the parts discussed in connection with the first form of switch. Also portion 56d is for a like purpose provided with a slot 66 to afford clearance in respect of the aforementioned post 6|.

A trigger type actuator 68 is provided to effect rectilinear movement of member 62, said actuator being pivotally supported on part 56 as later described. Actuator 68 is substantially U- shape in transverse vertical cross section and comprises parallel depending side portions 68a and 68b and a connecting portion 68C. The portion 68C, like the portion 58 of the trigger actuator aforedescribed, is.concaved in longitudinal Vdimension to provide for good finger grip. Portion 68c is depressed at a point thereon to provide a boss between the portions 68"L and 68b to afford retention of the upper end of the spring 59.

Portion 68a has an extended portion 68e which is in a coplanar relation therewith and as best shown in Fig. 7 portion 68e has an open notch 68 formed therein. The notch 69 receives post 6| of part 56d with sufiicient clearance to permit desired movement of part 68e. Also notch 68 receives a post 61 fixed to part 62c of reciprocating member 62, the part |58e by virtue of the slot having extensions |58r and 688 to be engaged alternatively with said post 61 subject to appreciable lost motion.

The portion 68b of the actuator has a portion 68h (Fig. 7) which bears at a right angle toward the portion 68, and vportion 68h together with portion 68 supports a reciprocable latch 10. The latch 10 comprises a push button 1I]a extending through an opening in portion 68, said push button having a portion 1I]b of reduced diameter extending through an opening in portion 68h. A metal washer 1I is secured to the free end of the reduced portion 10b on the outer side of portion 68h, as by upsetting of the end of the por-- tion 10. The washer 1I limits upward movement of the latch which is biased to such limit by a coil compression spring 12 disposed about the part 1I)b to bear at one end against the portion 68h and at its opposite end against the shoulder formed at the junction of portions 10 and 16h.

A pair of alined openings extending through the portions 68 and 68b are provided to accommodate the shank of a pivot pin 13 which is rigidly secured to the portion 56d of member 56. The pin 13 is provided with a reduced end portion projecting through an opening in portion 56d and the part of said end portion extending beyond portion 56d is upset to rivet the pin to said portion. A washer like spacer 14 is disposed about the shank of pin v13' between the portion 56d of member 56 and the adjacent surface of the portion 68a of actuator 66. The portion of pin 13 which extends beyond the outer surface of the portion 68b of actuator 68 is peripherally grooved to accommodate a horse shoe shaped snap-on Washer 15 of a well-known type. The washer 15 when snapped in place on pin 13 overlying the outer surface of portion 68b prevents movement of actuator 68 axially of pin 13. The aforedescribed alined Openings in portions 68 and 68b are of slightly larger diameter than the diameter of the shank of pin 13 so as to afford free pivotal movement of actuator 68 about said pin.

As aforedescribed, the portion 56 of member 56 has formed therein the circular openings 64 and 65 to accommodate screws or bolts for securing the switch unit within a tool handle or housing. The portion 56b is provided with two openings 16 and 11 which are located therein in relatively similar positions to the location of openings 64 and 65 in portion 56. Portions 56h and 56 are respectively thickened for 'a certain distance about their openings 64 and 16 and said openings are threaded.

As the switch stands in Figs. 7 and 8 it is in its normal circuit interrupting condition; vspring 59 being of suiiicient strength to overpower the springs associated with the movable contactors in the base I5.

When the trigger actuator 68 iS pivotally moved against the bias of spring 59 in the counterclockwise direction as viewed in Fig. 7, it moves without effect until its extension 68I engages with the posi-l 61. Further pivotal movement of the actuator then causes the member 62 to slide to the right as viewed in Figs. 7 and 8. When member 62 is moved sufficiently far to the right its portion 62b moves out of engagement with the portion 26 of cam 26 onto the portion 26d of the latter. Thereafter member 62 is caused to be moved farther to the right with more or less snap action by the bias of the springs of the movable contactors in the switch base I as aforedescribed in connection with the form of switch illustrated in Figs. 1 to 6. Accordingly circuit completing condition is effected within the base I5. The snap movement of member 62 to the right causes the post 61 to move out of engagement with the extension 68f and to 12e-engage extension 68g of actuator 66. The re-engagement of post 61 with extension 68g provides an audible signal and also a tactilly perceptible signal which is transmitted through actuator 68 to afford an indication that the switch has been operated to circuit completing condition.

If actuator 68 is pivotally moved in the counterclockwise direction to a certain point farther than is necessary to effect circuit completing condition of the switch, and the latch 10 is de- -pressed to its limit against the bias of spring 12 and held there while actuator 68 is released, the shank 1I)b of said latch and the washer 1I will engage and bind against the post 6I effectively latching actuator 68 in a depressed position thereby insuring that the switch will be maintained in its circuit completing condition. In order to release the latch 10, it is merely necessary to slightly depress actuator 68 pivotally in the counterclockwise direction andlatch 16 will then be released to move upwardly out of engagement with post 6| under the bias of spring 12.

If actuator 68 is released for free pivotal movement in the clockwise direction under the bias of spring 59 the switch will accordingly be returned to its normal circuit interruptingV condition shown in Figs. 7 and 8. Y

As will be noted the trigger actuators and associated operating connections aforedescribed for the switch assemblies shown in Figs. 1 to 6 and Figs. 7 and 8 respectively are so arranged and mounted with respect to the switch bases I5 that they are conned between boundaries comprising the outer surfaces of members 38 and 56. as the case may be, and -the outer surface of the rib I5b of the switch bases. Such arrangements afford compact switch assemblies which may be accommodated within a wide variety of tool handle housings or receptacles.

The switch illustrated in Fig. 9 is identical with that of Figs. 1 to 6 in respect of the insulating plate 44 and all of the parts positioned therebelow with the exception that the wiring lug 33, screws 35 and 36, rivet 34, and insulating member 45 are omitted and the recess I5g is not broached through to the recess I1 in base I5 as aforedescribed. The switch assembly of Fig. 9 differs in respect of its operating superstructure which is a preferred form 'of threehole mounting, toggle lever type superstructure.

The superstructure of the switch of Fig. 9 comprises a one-piece stamped sheet metal cover plate 18 having a centrally located bulge portion in which is secured a hollow metal bushing 19. A toggle actuator is pivotally supported within bushing 13 on a Ypin 8| and has an end portion adapted to slidablyf engage with the portions 26 and 26c1 of cam 26. A conventi-onal form of three-hole mounting bracket 82 is positioned over cover plate 18 and is provided with a suitable central ,opening to accommodate the bulged portion of cover plate 16 and is also provided with suitable threaded openings adjacent end extremities thereof to afford securement of the switch assembly in suitable housings or receptacles. Plates 82 and 18 are secured together-with an insulating plate 83 and diaphragm 21 in assembled relation to the upper surface I5a of base I5 by screws 84, 84 which are riveted over the upper surface of plate 18.

As will be understood pivotal movement of the lever 86 to the right as viewed in Fig. 9

ll will eifect circuit interrupting condition of the switch, the same being' in circuit Acompleting condition as it stands in Fig. 9;

The modified form of switch shown in Fig. l is identical with that of Fig; 9 in respect of the cover plate I8 and all parts-positioned therebelow. The switch of Fig. 10/ differs in respect of having a one-hole mounting, toggle lever operating superstructure somewhat similar to a form of operating superstructure disclosed in the Krieger' patent.

The operating superstructure ofy the switch of Fig. k10 comprises the cover platel 18 aforedescribed having a centrally located bulged portion in which is secured an externally threaded, hollow cylindrical bushing 85. A toggle lever actuator 86 is pivotally supported within bushing 85 on a pin 81 and yan enlarged hemispherical end portion thereof is adapted to slidably engage with the portions 26 and lli of cam 2B ywhen actuator 86 is pivotally moved Vabout the pin 81. Plate 78, insulating plate 83I and diaphragm 21 are secured in assembled relation to the upper surface of base l5 by the rivets 88, 88 which are only partially shown in the drawmg.

As will be understood the switch' is operable in the same manner as aforedescribed for the switch shown in Fig.,v9. ,Y

What I claim to be new and desire to secure by Letters Patent is:

1. In combination, a'molded insulating base having formed therein a main recess and an auxiliary T-shaped recess'of relatively shallow depth jointly opening to one surface of said base and said recesses being otherwise closed, said iirst mentioned vrecess communicating with said T-shaped recess, a flexible elastic sheet overlying the upper surface of said base to afford a substantially dust-tight closure for said recesses, said sheet havinga relativelysmall opening formed therein, a one-piece punched and stamped sheet metal cam member having a flat T-shaped portion positioned within said vlfshaped recess for pivotal support'thereby, a second portion extending from saidT-shaped por-- tion and projectingroutwardly with Hl-'Snug fit through the opening` in said sheet, a third ,portion extending from the outerfendV of said second portion in overlying relationship` to, said portion first mentioned, and ya 'fourth portion extending from said third portion'towar'd said portion iirst mentioned, stati-onary Tand movable contacts positioned within said iirstmentioned recess, means for normally biasing said movable contacts into a givenirelationship to the sta-y tionary contacts, an insulating member continuously engaged by themovable contacts and continuously engaged with the llirstfmentionedl portion of said cam member, acoverplate overlying said sheet and said insulating base, and fastening means securing said cover plate, said sheet and said base in assembled relation.

2. In combination, a molded insulating base' having formed therein a main recess and an auxiliary T-shaped recess of relatively shallow depth jointly opening to one surface of said base'Y and said recesses being otherwise-closed, saidfirst mentioned recess communicating with Ysaid. T- shaped recess, a flexible elasticsheet overlying the upper surface of saidbase tov afford ansub stantially dust-tight closure for said recesses, said sheet having a relatively small opening `formed therein, a one-piece punched andv `stampedsheet metal cam member having a flat T-shaped por tion po'sitionedwithin said T-shaped recess for pivotal support thereby, a second portion extending from said T-shapedportion and projecting outwardly with a snug fit through the opening in said sheet, a third portion extending from the outer end of said second portion in overlying relationship to said portion first mentioned, and a fourth portion extending from said third portion toward said portion first mentioned, a plurality of sets of stationary and movable contacts, said movable contacts being normally biased into engagement with said stationary contacts, a movable contact operator underlying said first mentioned portion of said cam member and through the action of said movable contacts normally biasing said cam member to an upper extreme position to permit engagement of said movable contacts with said stationary contacts, a flat insulating plate overlying said elastic sheet and having a relatively large central opening formed therein, a' cover and support member overlying said insulating plate, fastening means to secure said sheet, said insulating plateand said base in assembled relation, and movable means having sliding'engagement with said third and fourth portions of said cam member, said movable means when moved into engagement with said third portion of said cam member' effecting movement of the same inwardly of said base to a lower extreme position to effect disengagement of said stationary and movable contacts, and said movable means when moved into engagement with said fourth portion of said cam affording release of the .same for movement to its upper extreme position.

3. In an alternating current controlling switch of the relatively slow-make, -slow-break type, in combination, a molded insulating base 4having a recess opening to one surface thereof only, a plurality of sets of stationary contacts located within said recess, a corresponding number of bridging contactors located within said recess and normally biased into engagement with the respective sets of contacts, a at plate of insulating material overlying the intermediate portions of the respective contactors and continuously engaged by the latter, a punchedand stamped sheet metal cam' member pivotally supported within said recess and continuously engaged by said insulating plate, an elasticrubber-like diaphragm secured to said surface of the base and overlying said recess torender th'e'same substantially dusttight, said sheet having a relatively small opening formed therein to accommodate with a close fit a portion of said cam member extending outwardly therethrough, the exposed portion of said cam member having a plurality of adjacent cam surfaces formed thereon, manually operable actuating means cooperating with one of said cam surfaces to permit movement of said contactors under their' bias tovtheir normally engaged position, and said actuating means cooperating with both of said cam surfaces to effect movement of said contactors to and retention thereof in their disengaged'posit'ion.

4. As an article of manufacture for use with electric switches having a cam operating member,\a switch operating superstructure compris'-` ing a one-piece sheet metal member having a portion in which is formed a rectangular substantially ilat bearing vsurface which is substantially longer than it is wide, said'member being adapted for mounting on the switch housing to form one side thereof, and another portion ex-' tending in the same direction a substantial distance from one end of said rst mentioned portion, a one-piece sheet metal switch operating lever having a at portion which has sliding engagement with said at bearing surface and a second portion extending a substantial distance therefrom in a parallel relation to said other portion of said member first mentioned, the first portion of said operating lever being adapted for operable engagement with said cam operating m'ember, a trigger type actuator pivotally supported on said other portion of said member rst mentioned, means affording a lost motion driving connection ybetween said actuator and said second portion of said lever, and spring means biasing said actuator to one extreme position at which said lever attains a given extreme position relative to said member rst mentioned, said actuator being movable against the bias of said spring means and when so moved initially moving a predetermined distance relative to said lever with lost motion, and said actuator thereafter during movement to its other extreme position eifecting movement of said lever to its other extreme position relative to said member first mentioned.

5. As an article of manufacture, an electric switch operating superstructure for switches having a cam oper-ating member comprising a onepiece sheet metal cover member having a portion of substantially inverted channel-shape and another portion extending a substantial distance from one end of said channel portion, a one-piece sheet metal switch operating lever having a substantially flat portion located within and having sliding engagement with said channel portion of said member and a second portion extending a substantial distance therefrom in a parallel relation to said other portion of said member, said rst portion of said operating lever being adapted for operable engagement with said cam operating member, a trigger type actuator pivotally supported on said other portion of said member in such a manner that its .pivotal axis is at a right angle to the plane of said nat portion of said lever, means affording a lost motion driving connection between said actuator and said other portion of said lever, whereby when said actuator is moved initially it movesa predetermined distance relative to said lever with lost motion and thereafter during continued movement of said lever said cam operating member may move independently of said actuator.

6. As an article of manufacture, an electric switch operating superstructure comprising a onepiece sheet metal cover and support member having a substantially inverted channel-shaped portion and another portion extending a substantial distance therefrom in an oiset parallel relation, a one-piece switch operating lever having a substantially flat portion located within and having sliding engagement with said channel portion of said member and a second portion extending therefrom in an oiset relation thereto, said second portion of said lever being positioned in an overlapping relation to said other portion of said member, a trigger type actuator pivotally supported on said other portion of said member in such a manner that its pivotal axis is at a right angle to the plane of said flat portion of said lever, means affording a lost motion driving connection between said actuator and said other portion of said lever, and spring means biasing said actuator to one extreme position at which said lever attains a given extreme position relative to said member, said actuator being movable against the bias of said spring means and when so moved initially moving a predetermined distance relative to said lever with lost motionl thereafter during movement to its opposite extreme position effecting movement of said lever to its other extreme position relative to said member.

7. In an alternating current controlling switch of the relatively slow-make, slow-break type, in combination, an insulating base, a plurality of sets of stationary contacts positioned on said b-ase, a corresponding number of bridging contactors normally biased into engagement with the respective sets of contacts, a member of insulating material overlying portions of the respective contactors, a cam member pivotally supported upon said base and continuously engaged by said insulating member, an elastic rubber-like diaphragm secured to said base and overlying said base to render the same substantially dust-tight, said sheet having a relatively small opening formed therein to accommodate with a close lit a portion of said cam member extending outwardly therethrough, the exposed portion of said cam member having cam surfaces formed thereon, manually operable actuating means cooperating with said cam to permit movement of said contactors under their bias to their normally engaged position and to eifect movement of said contactors to and retention thereof in their disengaged position.

GEORGE J. MEUER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,441,525 Presgraves et a1. Jan. 9, 1923 1,536,086 Douglas May 5, 1925 1,657,040 Schmid Jan. 24, 1928 1,912,607 Watts June 6, 1933 2,151,910 Graubner Mar. 28, 1939 2,366,474 Bentley Jan. 2, 1945 2,418,759 Crimmins Apr. 8, 1947 2,429,448 Bakke Oct. 21, 1947 2,437,339 Webster Mar. 9, 1948 2,442,164 Ferris May 25, 1948 

